Troubleshooting
3
Subject to modifications resulting from technical improvements!
Buderus Ltd. • http://www.buderus-domestic.co.uk
54
Servicing manual for wall-mounted condensing gas boiler 600 Series 11S/19S/24S/24C • Issued 02/2006
3.1.14 Checking the circulation pump
z
Remove screw plug on circulation pump (fig. 62).
z
Turn the UBA mains power switch to “
I
”.
z
Check to ensure that the circulation pump is running.
The circulation pump’s running mechanism may become
blocked if the heating system has been out of use for an
extended period.
Use a screwdriver to rotate the circulation
pump in its normal running direction
and release the
blockage in question. If this procedure does not work,
replace the circulating pump.
z
If the circulation pump is working correctly, screw the plug
back in.
3.1.15 Replacing the circulation pump
z
Disconnect the system from the power supply.
z
Shut the servicing cock.
z
Drain the 600 Series 11S / 19S / 24S / 24C as per the
"Installation and Servicing Instructions".
z
Loosen the screw on the terminal box (fig. 63, item 2) of the
circulation pump and open the terminal box. Note the
wiring layout, and loosen the cables (fig. 63, item 1).
z
Loosen the screw-in connections on the circulation pump
(fig. 63, item 3) and remove the pump.
z
Fit new pump and connect to system.
z
Connect cables in previously-noted order inside terminal
box, close terminal box and screw shut.
z
Connect system to mains power supply.
z
Open servicing cocks.
Fig. 62 600 Series 11S / 19S / 24S / 24C:
Checking the circulation pump
Fig. 63 600 Series 11S / 19S / 24S / 24C:
Replacing the circulation pump
3
2
1
NOTE
Fill the 600 Series 11S / 19S / 24S / 24C and
purge the system of air as indicated in the
installation and servicing instructions.
